Tandem bicycles are well known in the art and are popular. With conventional tandem bicycles, the pedals are connected to a common drive chain for pedaling the bicycle. As such, both cyclists, when pedaling, must do so at the same rhythm.
Tandem bicycles are also relatively long and thus difficult to transport, particularly on small automobiles. On the contrary, two single bicycles can easily be stored side to side on most conventional bicycle racks which may be mounted on an automobile.
One can couple two single bicycles together to form a tandem to thus provide the advantages of a tandem bicycle. However, the coupling of the two bicycles to form the tandem bicycle is difficult to do in a manner in which a stable arrangement is reached.
The prior art does suggest that one can connect two single bicycles to provide a tandem bicycle arrangement. One such arrangement is shown in U.S. Pat. No. 4,458,908 issued in 1984 which shows two standard bicycles connected by removing the front wheel and fork of the rear bicycle and placing an adapter on the frame of the rear bicycle which is then mounted to the rear axle of the leading bicycle. The desirability of connecting two bicycles together to form a tandem bicycle is exemplified by U.S. Pat. No. 1,300,343 to Carswell which issued in 1919 and which shows another arrangement wherein a tandem bicycle arrangement is achieved. In this patent, the tines of the fork of the rear bicycle are coupled to a coupling link which is a forged tee having a ball bearing hob into which the fork connects. Still further examples of proposals in the prior art for tandem bicycle arrangements are exemplified by U.S. Pat. Nos. 4,307,893; 4,261,592; and 5,039,120.
The prior art does suffer from certain disadvantages. In some instances, the front wheel of the rear bicycle must be removed and then stored which is an inconvenience. The combination of two single bicycles does pose certain stability problems. Thus, if the area proximate the seat of the lead bicycle is connected to the portion adjacent the handle bar of the trailing bicycle by a cable type arrangement, the assembly is unstable when the cable is stretched out. However, the rear can never do more than provide is own mode of power--i.e. it can not assist in pushing the leading bicycle.
The use of a rigid bar having a universal joint or the like does not assist. If the trailing bicycle pushes in a direction other than the direction in which the bicycles are traveling, an oblique reaction force is exerted which tends to incline the bicycle toward the outside. The cyclist may attempt to correct this by turning the handle bar one way or another to provide a certain degree of stability. However, the two cyclists are generally not able to coordinate their movements.